2 lbs starchy potatoes, such as King Edward or Maris Piper, peeled and thinly sliced
2 cups heavy cream
1 cup whole milk
3 cloves garlic, minced
1/2 teaspoon ground nutmeg
1 teaspoon salt
1/2 teaspoon black pepper
1 cup grated Gruyere cheese, optional for a golden crust
1 tablespoon butter for greasing the baking dish
2 sprigs fresh thyme for garnish
Instructions
Preheat your oven to 325 degrees Fahrenheit. Generously grease a large baking dish with the butter, ensuring you cover the bottom and all the sides to prevent the cream from sticking as it bubbles up.
Peel the potatoes and slice them into very thin rounds, about one eighth of an inch thick. I highly recommend using a mandoline slicer for this step to ensure every piece is uniform, which helps the dish cook evenly through all the layers.
In a medium saucepan, combine the heavy cream, whole milk, minced garlic, nutmeg, salt, and pepper. Heat the mixture over medium heat until it just begins to simmer, then remove it from the heat. This step allows the garlic and spices to infuse the liquid before it even hits the potatoes.
Arrange a layer of potato slices in the bottom of the prepared baking dish, overlapping them slightly like shingles. Pour a small amount of the cream mixture over the layer. Repeat this process until all potatoes and cream are used, finishing with a final pour of cream over the top.
Cover the dish with foil and bake for 45 minutes. Remove the foil, sprinkle the grated Gruyere cheese over the top if you are using it, and bake for another 30 minutes. The potatoes should be tender when pierced with a knife, and the top should be a beautiful golden brown color. Let it rest for 10 minutes before serving so the sauce can set.
